Synthetic oil

my fuel economy increases when i'm near the end of my oils life. so far, if there is any difference in normal mpg, it's minimal. 1 mpg if that. but... i'm using different wheels which make things harder to calculate with my car.

 

Sounds like the oil is shearing down. It's quite common for a conventional 5W-30 oil with polymer additives to experience shear with use. It may shear down to a 5W-20.

Leave it in long enough and it will then thicken up quite a bit, say to a 20W-40. Oil is neat stuff, isn't it?

I would much rather run a stable synthetic that stays in grade. I don't know why folks were so scared of Mobil 1 0W-20 that they refused to buy it and Mobil pulled it off the market.

True it's a SAE 20 at operating temp, but it's a *stable* SAE 20.

I think at most you may gain 4-6 MPG running a good synthetic. Over 5,000 miles, see if the potential fuel economy increase pays for the synthetic.

Of course, if you never want to worry about sludge or varnish buildup, and you intend to keep the car a long time, then run the synthetic.

 

What is a good brand synthetic oil?

When I have my first oil change, will I have to bring my own oil to the dealership if I want a synthetic oil? If so....what do I buy?

 

I've had synthetic in my Pri for about 200 miles now. It's hard for me to gauge just what it's doing, my husband took the car to work with him to change the oil and took it out to 'play' with it... dropped my MPG down to 43 (from about 48) in one day. I've been able to increase the average more easily than expected, even with 350 miles on the tank. I'll report back after my next tank.

 

this question is like asking what condoms to buy. It's a personal choice decision. I personally use Mobil 1 5/30 and several others have as well. To say I see a big mpg difference, no, but my intention is to keep this car for a long time, so the added longevity provided by synthetic should help me achive that goal.

 

All very true. However, it must be noted that surveys show Mobil 1 5/30 ribbed gives the Prius a more satisfying experience.

 

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:lol:

 

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Some Toyota dealers also sell Mobil 1, at least around here they do. But it's at least 70 cents a litre more than Canuck Tire or Wally World.

Mobil 1 seems to be a favorite, it's reliable and works as advertised. A lot of folks swear by Amsoil, Redline, Royal Purple, etc. Those cost a lot more.

I'm leery of most of Castrol's "Syntec" offerings as they really aren't "true" synthetics, with the exception of the made in Germany 0W-30. Wally World has their own label of synthetics, but again who knows how it's made?

 

I am currently using Mobil 1 5W30. I believe I've seen a gain of about 2 mpg, which isn't much, but it does help. I'm not doubtful about the quality of Mobil 1, and I'm sure there are a number of other true synthetics out there that are just as good, but I think I'm going to stick with what I know, for now.

 

The AMSoil site has a lot of information about synthetic oils [web:38cbd4977c]http://www.amsoil.com/[/web:38cbd4977c].

It looks like synthetics are well worth the extra cost. If you decide to go with conventional oils, use an oil with the lowest weight spread ie 5w30 rather than say 10w40.

 

Sorry I nly meant to put in a link.